Grand Coulee Dam: Impacts on fish

Of all the impacts
that caused extinctions of Columbia River Basin salmon and steelhead, dams were
the most significant. And the most significant of the dams, at least in terms of the number
of known runs that were extinguished, is Grand Coulee.

The
dam wiped out runs that spawned in tributaries that drained into the Columbia
from that point, river mile 596, to the headwaters, a distance of 645 river
miles. Adding the tributary miles where salmon spawned nearly doubled the distance.
The Bureau of Reclamation, which built the dam, was aware of the impact Grand
Coulee would have on salmon and steelhead and took steps to compensate for the
losses through the construction of hatcheries. This was complicated,
however, by the fact that the upper Columbia salmon runs had been declining for
years before the dam finished them off.

The Bureau contracted with the Washington Department of Fisheries to assess
the runs and recommend a means of preserving them. The resulting 1938 report,
issued by B.M. Brennan, director of the Department, detailed the decline of
Columbia River salmon from multiple causes. The report contained
recommendations for preserving and relocating the salmon and steelhead runs — the North Central Washington Upper Columbia River Salmon Conservation Project.
The cost was estimated at $2.6 million, which would be paid from the Grand
Coulee construction fund. The plan called for trapping adult fish at Rock
Island Dam and transporting them in tank trucks to release points in rivers and streams below Grand Coulee and
also, eventually, to a hatchery that would be built at Leavenworth, on a
Wenatchee River tributary called Icicle Creek. From there, juvenile fish
eventually would be transported to release sites throughout north central
Washington.

It
was an ambitious plan, but it did not appear to attract broad public interest.
In the report, Brennan noted general public indifference regarding the plight
of fish and, conversely, public enthusiasm for Grand Coulee Dam, which then was
three years from completion but already had blocked the river. In the
introduction of the report Brennan wrote:

“The fishery of the Columbia River has been
decreasing slowly since the turn of the century. The constant inroads of
civilization have continually worked to the detriment of fish populations.
First irrigation diversions, then small hydroelectric dams on several
tributaries, then more and larger irrigation diversions, over-fishing by the
commercial interests, increasing sport fishing, gaffing of fish on the spawning
grounds, and increasing industrial and domestic pollution bringing pressure
constantly against the fish populations have slowly decreased their former
abundance. So many factors were at work in so many ways, that the public’s
attention was never riveted for any length of time on the decreasing value of
this enormous natural asset.

“.
. . In the first burst of enthusiasm that the whole Northwest felt at the
culmination of its plans, the fact that the construction of this dam would
strike a serious blow to the Columbia River fishery was overlooked by the
general public. When the plans for the high dam finally were approved, it
became apparent that salmon could not be put over a dam of this height as they
had been at the much lower Rock Island and Bonneville dams. The stock of salmon
spawning in some 1,100 miles of river and tributaries was to be permanently
destroyed. Further study revealed that the alternative methods for preserving
these runs would be extremely expensive, if they were possible. There was a
feeling that the vast economic gains to be derived from this project should not
be endangered by consideration of the fish. It was even felt in some quarters
that the fish were not worth the money that it would take to preserve them.

“.
. . The irrigation and power developments in connection with the Grand Coulee
project are confiscating valuable prior rights to the river held by the fish
and therefore by the commonwealth to which the fish belong. It is only just
that these developments pay compensation for these confiscations; that is, the
cost for the apparatus necessary to perpetuate these runs should be included as
a part of the capital investment of the dam and irrigation system, and the
operation of this apparatus should be included in the operating costs of the
irrigation and power developments.”

Grand
Coulee Dam thwarted the grand plans Washington had to rebuild the Columbia
River salmon fishery. In discussing possible methods of protecting salmon and
steelhead from the impact of the dam, Brennan noted: “There had been a
systematic progression of improvements up the river with the idea in mind of
bringing back every portion of the Columbia River watershed under the
jurisdiction of the State of Washington into its former condition of
productivity. . . [but] Grand Coulee Dam completely upset a large share of
these plans and work.”

According
to Brennan’s report, “the pressure of public opinion” forced the construction
of fish protective devices 400 miles downriver at Bonneville Dam. The pressure
of public opinion also may have played a part in the decision of the Bureau of
Reclamation, then called the Reclamation Service, to preserve some remnant of
the salmon and steelhead that its dam at Grand Coulee would wipe out. Making
the decision was the easy part; making it happen was the hard part. As Brennan
notes in his report for the Reclamation Service, “there was left the question
of what was the best way to take care of the fish.” Little was known, he wrote,
and he might have added that there was little time. 1938 was the year
construction at Grand Coulee Dam finally would cut off the river to migrating
fish.

An
investigation was needed — of fish behavior, migratory patterns, abundance,
spawning locations, tributary water flow and temperature. So many things.
Because the state couldn’t afford such a study, the Reclamation Service gave
the state $25,000 for a one-year investigation. The state didn’t receive the
money until the spring migration of juvenile salmon nearly was over. Only six
months of field study was possible. Brennan did the best he could.

He
began with the obvious — the dam itself. Fish passage would be impossible, he
concluded. “The construction of the low dam, as originally planned, would have
presented no insurmountable obstacles to caring for the fish,” [but] “the
present plan of constructing a dam with 350 feet of head completely alters this
picture. For several reasons it is impractical, if not impossible, to put fish
over a dam of this height and maintain a run with the project under its
ultimate development.”

Brennan
cited five reasons why fish passage at Grand Coulee would not work.
First, water immediately below the dam could be expected to fluctuate as much
as 40 vertical feet within periods of minutes, depending on power production.
It would be difficult, at least, to build a fish ladder that would operate
efficiently in such conditions, he reasoned. Second, because the dam likely
would be spilling water in the summer when the fish arrive on their upstream
journey to spawn, the fish, which are attracted to agitated water, likely could
not find the ladder entrance. Third, in the spring and early summer, when the
juvenile fish are heading to the ocean, the giant irrigation pumps would be
sucking up to 18,000 cubic feet per second from a spot directly behind the dam,
an amount of water Brennan likened to the flow of the Skagit River in western
Washington. “It will be a practical impossibility to screen these pump intakes
with mesh fine enough to keep the young fish out,” he wrote. “Large numbers [of
young salmon and steelhead] would be pumped into the irrigation system to
perish.” Fourth, water would not spill over the dam all year round, and so at
certain times of the year — the fall, for example — young fish would be stuck
behind the dam, where there likely would not be enough food for their survival
through the winter. In the spring, when the river is higher, young fish swept
over the dam would face a “. . .400-foot slide down the concrete face of the
dam,” and “...all or mostly all would be killed.” Fifth, even if the fish could
be carried over the dam in a column of water and not touch the concrete, where
they would be battered and descaled, “. . .it is questionable how safely they
could negotiate this 350-foot fall.” That’s an understatement.

So
fish passage was impossible, or at least so improbably expensive and
life-threatening that it wasn’t worthy of further consideration. But there was
a larger problem than the concrete wall at Grand Coulee. The larger problem was
with the fish themselves. These fish did not spawn at the dam, or anywhere near
it. Some went all the way to the headwaters, and most spread out into myriad
tributaries in Washington and southeastern British Columbia. There was almost
no knowledge of how many salmon, as a percentage of those that cross Rock
Island Dam, spawned above Grand Coulee. Many were believed destined for the
Arrow Lakes, but that area was remote and virtually inaccessible by
road and so a difficult place to count fish. Anecdotal evidence was useful,
however, and the authors of the report noted a conversation with “an old
Indian” at Kettle Falls on August 6, 1937, about sockeye salmon, also called blueback: “Although he did not know the fish by the name blueback, he
recognized them when confronted with the specimens that had been caught. He
said that many years ago there used to be large runs of blueback at Kettle
Falls, and the Indians used to congregate there to catch them, but in recent
years the runs had been so small that the Indians had not fished them.”

Based
on this report and others, including interviews with residents near the Arrow
Lakes, the biologists estimated that “more than 85 percent” of the sockeye
crossing Rock Island Dam were destined for rivers other than the Wenatchee and
the Okanogan, the only two sockeye rivers downstream of Grand Coulee. Sockeye
are unique among salmon in that they spawn and rear in and around lakes, such
as Lake Wenatchee and Lake Osoyoos, on the Wenatchee and Okanagon rivers,
respectively. The problem for the biologists, of course, was that these fish,
and other salmon that spawned in the upper Columbia, were not ready to spawn
when they reached Rock Island Dam. “The salmon and steelhead when they reach
[Rock Island Dam] are not ripe and will not spawn for several months,” Brennan
wrote. “The blueback pass over the dam in July and August and do not spawn
until the latter part of September. The first Chinook salmon reach Rock Island
in April and do not begin spawning until the latter part of August. The fall
run of steelhead pass Rock Island in September, October and November and do not
spawn until the following late winter and spring.”

His
solution was to hold the salmon, somehow, until they were ready to spawn and then
transfer them to Columbia tributaries downstream of the dam — the Wenatchee,
Entiat, Methow and Okanagon. But what about the salmon and steelhead that spawn
in those rivers? Would they be held, too? It would be impossible to tell them
apart, and so all must be collected together. But where would they be taken?
And when? Each population would have a unique run timing. Imagine each
population as an alarm clock set to go off at a different time. There was no
acceptable water supply near Rock Island Dam for rearing ponds, but there was
sufficient clean water and a good location at Icicle Creek, a Wenatchee River
tributary near the town of Leavenworth, 42 miles from the dam by highway.

Brennan’s
plan was to collect adult salmon and steelhead at Rock Island Dam and haul them
by truck to release sites on the Wenatchee, Okanogan, Methow and Entiat rivers.
Ultimately, the Leavenworth hatchery would produce fish to supplement the runs
in these rivers. Brennan knew it would be impossible to naturally produce as many
fish in the 677 miles of those four tributaries below Grand Coulee as in the
1,100 miles of tributaries above the dam where most of the captured fish would
have spawned. So hatchery production would supplement natural production.
“Instead of a natural crop of young fish from these four tributaries, it
becomes necessary to produce an intensified crop far in excess of that which
could be produced naturally,” he wrote. And these fish would be different from
other hatchery fish. They would be bigger — closer to the size they would have
been had they been hatched above Grand Coulee and migrated to the sea
naturally. “Such a program may offset the damage done by Grand Coulee Dam;
ordinary hatching and liberation in the young fry stage cannot,” he wrote.

These
were not pristine rivers. In fact, they suffered some of the same problems as
modern-day rivers. For example, the Okanogan River was “a sluggish, slow-moving
stream” whose chief salmon-producing tributary, Salmon Creek, was so heavily
pumped for irrigation “that it’s rehabilitation for salmon reproduction is
impossible,” Brennan wrote. The Methow supported salmon, but the small size of
the run likely was due to the impact of a hydropower dam constructed at its
mouth in 1915 and removed in 1929, and the fact that the river “has a
particularly large number of irrigation diversions.” The Entiat, in contrast,
was an excellent salmon river — with few salmon. Like the Methow, the Entiat
once had a power dam near its mouth, which later was removed. The dam blocked salmon,
and the damage was done. The Wenatchee River’s salmon runs suffered from large
irrigation and power diversions. Each of the rivers had unscreened diversions
that were lethal to juvenile fish.

It
wasn’t ideal, but it was all they had to work with. The trapping and hauling
began in May 1939. Fish were trapped at Rock Island Dam, transferred to a tank
truck and then transported to releases sites — two in the Wenatchee drainage
(Icicle Creek and a spot on the main river called Monitor) and one each on the
Methow, Entiat and Okanogan rivers. In the process, the biologists learned a
good deal about salmon. For instance, they learned that even though water
temperature in the unrefrigerated tank truck rose steadily, there seemed to be
little effect on the fish. In the three-hour hauls to Oroville, on the
Okanogan, and Twisp, on the Methow, the water temperature would rise by as much
as 16.2 degrees. One time, the water temperature on arrival at Oroville was
79.7 degrees, about 12 degrees above lethal for salmon. But, according to the
report, “these fish were certainly as lively and appeared, outwardly, at least,
as healthy as any fish hauled.” There was concern, however, for the viability
of the eggs and sperm following such a temperature shock.

The
biologists also learned about the importance of properly oxygenated water
during transport. During one haul to Icicle Creek, the oxygen pump broke down
during and 29 out of 30 salmon were dead on arrival. In general, though, the
biologists were impressed with the resiliency of the fish. Upon releasing fish
from the tank truck, many were noted with scars, gouges and other wounds, but
these fish would revive in the water and swim off apparently unaffected.

They
were hearty fish — they are hearty fish today — but in 1938 they faced a
gauntlet strikingly familiar to the one modern salmon face. There were dozens
of gravity diversions for irrigation on each river — 73 total on the
four rivers, not including the complete diversion of Salmon Creek, plus diversions
on the Okanagan in British Columbia above Lake Osoyoos. Also, there were
numerous irrigation pump stations that lacked fish screens. All told, the
gravity diversions alone accounted for all but roughly 100 cubic feet per
second of the combined average flow of all four rivers. As happens today,
rivers can be overappropriated, and when flows are below average, the rivers
can run dry. There were diversions for hydropower dams, too — three on the
Wenatchee River alone.

“The
thousands of young fish diverted are practically all killed when the ditch is
dried up in the fall,” according to the report. “Also, the diversion of this
quantity of water actually renders some of the streams (particularly the
tributaries of the Methow) unfit for the upstream migration of the adults in
the fall, as well as strongly decreasing the feeding and shelter area for the
young fish.”

This
was the habitat that was supposed to rebuild the fish runs lost to Grand Coulee
Dam. The desperate situation — one might say the seeming futility of the
restoration effort — was not lost on the men who were handed this difficult
task in 1938. Brennan’s report comments:

“To the most casual observer it is an
increasing source of wonder that any adult salmon are able to reach the
spawning grounds and, once reached, that enough of the small salmon are able to
return to the sea to maintain a run of any size. As a matter of fact, the
salmon runs into these streams are at present in an extreme state of depletion.
Irrigation and water power developments are the two principal causes. Mining
and domestic pollution are not yet important factors, but are potentially so.”

In
March 1940, the trapping and hauling began for the second year. Some of the
fish were taken to the Leavenworth hatchery, now completed. On August 6, 1941,
the first salmon reared at the hatchery, 50,000 fingerling Chinook, were trucked
to the Entiat River and released. Later, other hatchery progeny were released
into the Methow, Okanagon and Wenatchee rivers, and by 1942 the adult progeny of
fish that had been trapped and transported up to three years earlier began
returning to spawn. The Bureau of Reclamation claimed victory in 1943 — the
same year no salmon or steelhead showed up at the base of Grand Coulee Dam
attempting to continue upriver — and sought to turn over the Leavenworth
hatchery and its related facilities to the U.S. Fish and Wildlife Service. By
1949, ownership had been transferred to the U.S. Fish and Wildlife Service.

While
it is true that salmon were returning to spawn, they were not returning in
numbers even close to pre-dam counts and, of course, none of these fish was
destined to spawn above Grand Coulee. In 1933, the year construction began at
Grand Coulee, 51,879 salmon swam through the fish ladders at Rock Island Dam. Through
1942, the highest count was 35,000, and most years were far lower. Paul Pitzer,
in his history of the dam, Grand
Coulee: Harnessing a Dream,
concludes it simply isn’t known whether the salmon transplant experiment was a
success. Other impacts damaged the salmon runs, including the construction of
new dams downstream, construction of irrigation systems on tributaries,
diseases at the hatcheries, overfishing and pollution. “In the 1930s, when the
dams were the highest priority, the salmon survived more through good luck than
government efforts,” he wrote.

Meanwhile,
north of the border Canada appears to have been truly indifferent to the loss
of salmon and steelhead from Grand Coulee. It is true that a few citizens spoke
against the destruction of the Canadian Columbia River runs at the public
hearings conducted by the
International Joint Commission at Trail,
B.C., and Spokane in 1941. But neither British Columbia nor Canadian federal
fishery agencies registered concerns at the hearings, and the citizens who
spoke seemed more interested in ensuring that the Americans who killed the runs
would provide replacement fish in compensation. In fact, the state of
Washington eventually built two hatcheries to release fish — trout and kokanee — into Lake Roosevelt as partial compensation for the loss of salmon and
steelhead.

Canadian
federal officials were not entirely silent on the matter, however. In October
1934, as the initial site preparations were underway at Grand Coulee, the
Canadian Legation in Washington, D.C., took note of the fact that the high dam — with no fish passage facilities
— meant ruin for Canadian Columbia River
salmon. The Legation expressed its concern in a letter to the federal Ministry
of Fisheries in Ottawa.

The
reply to that letter, signed by Deputy Minister William A. Found, concluded:
“The assumption that there is no commercial salmon fishery on the Columbia
River in Canada is correct, and hence Canadian interests in that respect will
not be affected if the dam at Grand Coulee is not equipped with fishway
facilities.”

Remarkably,
the Canadian government wrote off Columbia River salmon because there would be
no adverse economic impact from their loss.

In 1936, three years after construction began, the Columbia River still was flowing over the foundation of Grand Coulee Dam. By 1938, the rising dam would block the river.
Credit: Spokane Public Library